This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Barmah Forest virus (BFV) is an arbovirus, member of Alphavirus genus of Togaviridae family. Currently, it is endogenous to Australia where it is one of the leading causes of viral arthritis and arthalgia. It is similar to Sindbis and Ross River virus in its clinical manifestations but is serologically different, with weak cross-reactivity to antibodies against Sindbis hemagglutinin and no reaction with monoclonal antibodies against Semliki Forest virus nucleocapsid protein. Our studies of BFV include production of subnanometer resolution 3D map of the virus and investigation into its structural similarities and differences with other alphaviruses. Since BFV is an alphavirus, we hope the high resolution map of the virus would be useful for studies of other alphaviruses, and, more generally, enveloped viruses.